Mineral oil composition



Patented Jan. 8, 1946 UNITED 'STATES PATENT OFFICE MINERAL OIL COMPOSITION Orland M. Reilf, Woodbury, N. J., asslgnor to Socony-Vacuum Oil Company, Incorporated, a corporation/oi New York No Drawing. Application August 2'7, 1943, Serial No. 500.275

9 Claims.

, cient in one or more respects so that their practical utility is limited even in the particular field for which they have been refined. For example, mineral oil fractions refined for use as lubricants have a tendency to oxidize under conditions of use with the formation of sludge or acidic oxidation products; also, the lighter fractions such as gasoline and kerosene tend to oxidize with the formation of color bodies, gum,etc. In order to prevent the formation of these products and thereby extend the useful life of the oil fraction,

it is common practice to blend with such oil fracfor the purpose of depressing the pour'point of mineral oil fractions which have been refined for use as lubricants. Most refining treatments provide oils containing a small amount of wax in the oils, which, without the added ingredient, would tend to crystallize at temperatures which render the oil impracticable for use under low temperature conditions. Additive ingredients have also been developed for improving the viscosityindex of lubricating oil fractions. In the case of internal combustion engines, particularly those operating with high cylinder pressures, there is a decided tendency for the ordinary lubricating oil fractions to form carbonaceous deposits which cause the piston rings to become stuck in their slots and which fill the slots in the oilring or rings, thus materially reducing the efficiency of the engine. Ingredients have been developed which, when added to the oil, will reduce this natural tendency of the oil to form deposits which interfere with the function of the piston rings.

It has also been discovered that certain types of recently developed hard metal allo bearings, such as cadmium-silver alloy bearings, are attacked by ingredients in certain types of oils, particularly oils of high viscosityindex obtained by various methods of solvent refining. This corroslve action on such alloys has led to the development of corrosion inhibitors which may be used in solvent refined oils to protect such bearing metals'against this corrosive action.

In the lighter mineral oil fractions'such as those used for fuel purposes, particularly in internal combustion engines, it has been found that the combustion characteristics of the fuel may be controlled and improved by adding minor proportions of various improving agents thereto.

The various ingredients which have been developed for use in mineral oil fractions to improve such fractions in the several characteristics enumerated above are largely specific to their particular applications. Therefore, it has been the practice to add a separate ingredient for each of the improvements which is to be efiected.

The present invention is predicated upon the discovery of a group or class of oil-soluble metal. organic compounds, which when added to mineral oil fractions in minor proportionswill improve the oil fractions in several respects. These multifunctional compounds are formed by the reaction of basic polyvalent metal salts of heavy alkyl-substituted aromatic hydrocarbon compounds and mercaptothiazoles and may be broadly designated as the metal mercaptothiazoles of basic polyvalent metal salts of alkyl-substituted aromatic hydrocarbons. All of the reaction products or compounds contemplated herein contain as characterizing groups: at least one polyvalent metal mercaptothiazole group (M-S-Z, wherein Z represents a thiazole group,

and an aryl nucleus substituted with at least one oil-solubilizing alkyl group and substituted with an atom or group represented by the symbol Q.

The most probable formula for the reaction products or compounds contemplated herein is:

, I (I) R.'r- M -s-z ,]d

' wherein 'I is an aromatic nucleus, either monoaliphatic ,or'allryl group having at least about thioester, keto, thioketo, alkoxy, aroxy, thioether,

polysulflde, aldehyde, thioaldehyde, oxime, amido, thioamido, carbamido, aralkyl, aryl, alkaryl, alkyl, halogen, nitro, nitroso, nitrosamino, amidine, imino, N-thio, diazo, hydrozino, cyano, cy-

anate, thiocyanate, azoxy, azo and hydrazo radicals; b is equal to the number of Y substituents attached to a single aryl nucleus T and is equal to a numeral from to 4; Q is a radical selected rrom the group consisting of wherein R represents a radical selected from the group consisting of aryl, aralkyl, alkyl and alkaryl, R." represents hydrogen, alkyl or aryl radicals and X, X and X" represent elements selected from the group consisting of oxygen and sulfur; M is a polyvalent metal; Z is a thiazole radical,

and may'be'substituted as hereinafter described; c is the number of mercapto-thiazole groups, s-z, and is a whole number from 1 to 4, and is preferably 1; and dis the number of -lc ez),]- groups attachedto an aromatic nucleus T and is a number from /3 to 2.

Although as indicated herein Q and Y may be aster/ea i any of the several groups enumerated above, particularl preferred or the Q groups are:

and particularly preferred oi the Y groups are the polysulflde groups such as the disulfide group.

Itwill be obvious that when no Y substituents are present (b=0), general Formula I becomes:

wherein all symbols are as defined above.

In general, the substituted aryl nucleus may berepresented by and-may be any organic radical characterized by a heavy alkyl-substituted aromatic group to which the polyvalent metal may be attached at the aryl nucleus either directly or through an intervening inorganic element or organic radical.

Some of the reaction products or compounds contemplated herein may have two or more alkyland -M(s-z I Y substituted aromatic nuclei such as those in which the aromatic nuclei (T) are interconnected by an ether, thioether, polysulfide or keto group represented by the symbol Y defined above. A particularly preferred reaction product or compound of this type is one in which two or more benzene nuclei are interconnected through one or more disulfide groups. As indicated above, M is a polyvalent metal and may be copper, beryllium, magnesium, calcium. strontium, barium, radium, zinc, cadmium, mercury, germanium, tin, lead, vanadium, chromium, manganese, iron, cobalt, nickel, ruthenium, palladium, platinum, aluminum, antimony, arsenic, bismuth, cerium, columbium, gallium, gold, indium, iridium, molybdenum, osmium, rubidium, selenium, tantalum, tellurium, thorium, titanium, tungsten, uranium and zirconium. Preferred of such metals, however, are the divalent metals, and of the latter, barium, is particularly preferred.

As described above, T represents an aromatic nucleus which may be monoor poly-cyclic. Typical nuclei contemplated herein are benzene, naphthalene, anthracene, phenanthrene, di-

phenyl, etc.

The symbol Z defined above as a thiazole group,

said reaction products or. compounds characterized by an aryl nucleus having these alkyl substituents are not only oil soluble but possess the added properties of improving the pour point and viscosity index of the oil to which they are added. Petroleum wax is a preferred source of the high molecular weight alkyl substituent, and for this reason, the preferred multi-functional reaction products or addition agents are referred to as "wax substituted. It is to be understood, however, that other equivalent long-chain aliphatic hydrocarbon compounds, such as ester waxes, high molecular weight alcohols, polymerized unsaturates typified by isobutylene polymers, natural and synthetic rubber, etc., may be utilized. In compounds of the preferred subclass, that is, those containing a wax substituent, the wax group cooperates with the aryl nucleus to which it is attached in imparting pour depressing and viscosity index improving properties to these agents. These preferred metal-organic compounds are capable of remaining uniformly dispersed in mineral oil either as a true solution or a colloidal suspension under normal conditions of handling and use. There appears to be, however, a critical zone or region in the degree of alkylor wax-substitution below which these compounds or compositions are not readily soluble in viscous mineral oil fractions. This degree of alkylor wax-substitution for the oilsoluble or oil-miscible metal-organic compound may vary over relatively wide limits, depending upon whether the aryl nucleus is monoor polycyclic and whether such nucleus carries other substituents such as represented by Y, and whether the thiazole radical, Z, carries substituent groups.

It should be understood that the wax group in the preferred sub-class may be polyvalent in nature, in which event each of the polyvalent wax radicals or groups will be attached to a plurality of aryl nuclei, each of which aryl nuclei has at least one Q' a]! substituent, and each of which may have attached to it one or more monovalent wax substituents and may, in addition, have other substituents such as represented above by Y.

Formula I above is, as aforesaid, the most probable formula by which the reaction products or compounds contemplated herein may be represented; the formula, however, is not completely self-explanatory, for the scope of the formula is much more comprehensive in view of the various ways by which an alkyl group and particularly a "wax group, or wax groups, may be attached to two or more aromatic nuclei (T). It should be borne in mind that (waxh, as represented by Rs. in Formula I, may be one or more monovalent or polyvalent aliphatic hydrocarbon groups of at.

least twenty carbon atoms or a mixture of such groups. Therefore, to illustrate more completely and more accurately the field of the invention. taking into consideration the polyvalent wax type of compound or composition, and also taking have the same significance described above under Formula I; R represents an oil-solubilizing alkyl or wax group as defined above in connection with general Formula I; 1: represents the valence of the alkyl or wax radical R, which has been found to be from one to four for best results in obtaining oil-miscible products; and e represents a whole number preferably from one to four, and indicates the total number of groups b I [4(Q ).)4] present in the molecule represented by Formula. II and which are attached to the aliphatic group or groups represented by R.

In the foregoing probable Formula II, which represents the reaction products or compounds contemplated herein as mineral oil improving agents,it will be observed that the reaction products or compounds represented thereby include those materials in which all of the wax" substituent (R) is monovalent (0:1 and e=1), or in which all of the "wax substituent is polyvalent (v and e preferably being equal to 2, 3 or 4). Since R is defined as always being "at least one" and may therefore include several such groups, it will also be observed that this general Formula II is inclusive of reaction products or compounds having aliphatic groups or radicals of different valences (preferably from 1 to 4) in the same molecule. Also it will be observed that in these reaction products or compounds when e is any whole number from one to four, the number of aromatic nuclei in the molecule may likewise vary from one to four. Therefore, it will be seen that the relationship between e and v in Formula II in its broadest construction is such that when 2 is equal to one, 12 is equal to one, and when e is greater than one, the valence v of at least one of the Rs is equal to e in order to tie the several nuclei of TS together, the valence of any remaining R's being any whole number equal to or less than e.

A simple type of reaction product or compound coming under general Formula II in which 0 and e are both equal to one and in which there is only one "wax substituent, R, may be illustrated by the following formula showing T for purposes of illustration as a monocyclic nucleus:

H (A) OH groups, may be represented by the following formula:

H H (B) HCC- g 311 H H H H Reaction products or compounds of the type satisfying general Formula II, in which R 'is polyvalent and v and e are both more than one and in which there is only one such polyvalent 4- aseavcc v Rgroup, me temhstrated by the following forcleus. as 'r. substituted with at least one mula:

. Q-M-Q-S-ZL]; [Q M(SZ).]a Q-M(S-z).].| Y. I -Q Y.- n a ncc-cn H H n v H H v In this same type of reaction product or combilizing alkyl group, such as a wax" group, and

pound indicated by Formula C, there also may with or withoutone or more of'the various Y be more than one R (wax) group (represented substituents. However. in preparing the oil-imby the chain), such reaction product or comproving products defined hereinabove, those conpound in which there are, for example, two polytaming at least one wax" (R) group, obtained valent groups being illustrated by the following by procedures in which wax-substitution is efformula: fected .with a chlorinated wa c by a Friedel-Graits H H n H n I nc-c 9 9-011 H H The possible molecular structure of reaction reaction, the final oil-improving product is usuproducts or compounds in which the aryl nucleus ally a mixture of different compounds corre- T is polycyclic will be obvious from the foregoing sponding to different values of e and o and to illustrative Formulae A to D inclusive and the different numbers of wax" (R) oup and for -QMSZig3'oup and at least one oil-solupossible molecular structure of compounds in this reason the products contemplated herein are which 12 and e are both equal to two and four described as reaction products as well as comwill be readily understood from the illustrative pounds.

Formulae C and D. The reaction products or compounds contem- Other possible molecular structures of reacplated herein are broadly defined as the mertion products or compounds coming under gen- 40 captothiazole reaction products of basic polyeral Formula II are those having a plurality of valent metal salts of alkyl-substituted aromatic R (wax) groups of difierent valences. Such a hydrocarbons, and are obtained herein by reactreaction product or compound may be typified ing mercaptothiazoles with basic polyvalent metby the following Formula E in which the symbols a1 salts of such organic compounds such that have the same significance as in the formula water is eliminated andthe desired reaction prodalbove: uct or compounds are formed. Such procedure H H H H H nc-c c 0-01;

C-CH H H With regard to the number of R groups going to may, for illustrative purposes, be represented by make up a single molecule, thi will vary with the the following reaction: extent to which it is desired to effect substitution of the nucleus with the alkyl or "wax derivative for obtaining the desired properties in the prodnot. It is, of course, limited to the number of T+Q M+OH)) replaceable hydrogens on the aromatic nucleus if, i which are available forsubstitution. As will be apparent to those skilled in the art, the maxie mum number of R groups which can be attached i to a single aromatic nucleus will vary as the wherein all symbols areas-hereinabove defined. nucleus is mono or poly-cyclic and also as the A general procedure which may be followed for nucleus is otherwise substituted. the preparation of-the reaction products or com- It will be understood that the oil-improving pounds defined hereinabove is illustrated by the agents contemplated by this invention may be following in which a typical aromatic, a hydroxypure compounds satisfying the probable formulae aromatic compo n is used. 'Ilhe hydroxy I and II above with a monoor poly-cyclic numatic compound is first substituted, or alkylated,

with one or more oil-solubilizins groups to the desired extent as by reacting said compound with a chlorinated paraffin wax in the presence of a Friedel-Crafts catalyst. The wax-substituted) compound so obtained is then reacted with two equivalents of a polyvalent metal hydroxide or of a basic metal alcoholate; or is then reacted with two equivalents of NaOH and two equivalents of a polyvalent metal halide whereupon the basic metal salt of the wax-substituted hydroxyaromatic compound is formed. The basic metal salt formed in this way, by definition, will have at least one valence of the polyvalent metal atom satisfied by an hydroxyl (-OH), radical. The basic metal salt isthen reacted with a mercaptothiazole to form the desired reaction product or compound of the'class defind above.

Where other Y substituents such as a sulfide or disulfide group, are desired, they are usually introduced into the aromatic compound by first forming the alkali metal salt, and reacting the latter with a sulfur halide before the correspond-- ing basic metal salt is formed. On the other hand, elementary sulfur may be reacted with the aromatic compound before or during the formation of the basic metal salt. It will be obvious to those familiar with the art that various modifying substituents as defined above by the sym- 1001 Y may be introduced by modifying the foregoing general procedure by the use of any of the well-known chemical methods. Such modifications will be apparent by Example In provided hereinafter.

Typical basic polyvalent metal salts of organic compounds which may be reacted with mercaptothiazoles to form the reaction products or compounds of this invention are disclosed in my Patent 2,197,835. The basic metal salts are described therein as metal compounds wherein at least one valence of a polyvalent metal, such for example as, a divalent metal, is satisfied by an hydroxyl group. A general method of preparation of these basic metal salts which is applicable to all polyvalent metals consists in the use of one extra equivalent of alkali hydroxide in the neutralization of the corresponding free aromatic acid or corresponding free hydroxyaromatic compound, etc., which is substituted with at least one R substituent, at least one Q group and which may or may not be substituted with Y substltuents, followed by treatment with an amount of polyvalent metal salt (preferably a halide) equivalent to the alkali hydroxide used. While this is the preferred general procedure of forming these basic metal salts, such salts are formed to a certain extent even when exactly equivalent amounts of reactants are used. Apreferred method of forming the basic salts of alkaline earth metals like barium and calcium consists in reacting the organic compound, which is substituted. with at least one B substituent, at least one Q group and which may or may not be substituted withYsubstituents, with two equivalents of the hydroxide or basic alcoholate. It is to be understood, however, that while we have pointed out preferred procedures for forming the aforesaid basic metal salts, the present invention is not to be confined to such procedures, for, as aforesaid, these basic metal salts may be prepared in any way known to the art.

To more fully describe the metal-organic compounds or compositions contemplated herein, the following typical procedures for the preparation of representative compounds or compositions are provided.

EXAMPLE I Rue-non Pnonvcr or Mrncerroaruzormszor: AND BASIC BARIUM PHENATE or WAX-PHINOL (3-14) (a) Preparation of basic biarium phenate of warphenol (3-14) A wax-substituted phenol prepared according to the procedure provided in my Patent 2,197,834, in which a quantity of chlorwax containing 3 atomic proportions of chlorine (14 per cent chlorine in the ehlorwax) is reacted with one moi of phenol, may for brevity herein be designated wax-phenol (3-14). Parenthetical expressions of this type (A-B) will be used hereinafter in connection with the alkylated hydroxyaromatic compounds to designate (A) the number of atomic proportions of chlorine in chlor-aliphatic material reactcd with one moi of hydroxyaromatic compound in the Friedel-Crafts reaction, and (B) the chlorine content of the chlor-aliphatic material. In the wax-substituted phenol referred to above, A=3 and 3:14. This same designation will also apply to the metal-organic compounds or compositions of this invention.

One hundred grams of wax-phenol (3-14) obtained as indicated above, dissolved in about 200 grams of mineral oil (Saybolt Universal Viscosity (SUV) of '87 seconds at 210 F.) were heated to about C. and 9.8 grams of BaO dissolved in methanol were added thereto. A solution of BaO in methanol assaying about 10% barium was used. The temperature of the reaction mixture was then raised to about C. to remove methanol and the remaining reaction mixture was filtered with the aid of Hi-Flo to obtain the finished product in approximately a 1:3 blend in mineral oil. The product, basic barium phenate of waxphenol (3-14), is formed by reaction of wax-phenol (3-14) with basic barium methylate (Ba(OH) (001-13)) the latter being formed when barium oxide (BaO) is dissolved in methanol.

(b) Preparation of reaction product of I (a) and mercaptobenzothiazole Two hundred grams of the mineral oil blend of basic barium phenate of wax-phenol ((3-14), obtained in 1(a), were reacted with 10 grams of mercaptobenzothiazole at about C. for two hours. Water was liberated during the reaction and removed as steam to ive the final reaction product.

The barium phenate used in this reaction had an alkalinity equivalent to 11 mgs. of HCL per gram of product, whereas the final product obtained with mercaptobenzothiazole had only an alkalinity equivalent to 3.4 mgs. of HCl per gram of product. This indicates that the final product is predominantly comprised of the mercaptobenzothiazole reaction product of the basic barium salt of wax-phenol (3-14) This product is identified hereinafter as Product 1.

EXAMPLE Ii REACTION PRODUCT or MERCAPTOBENZOTHIAZOLE AND BASIC BARIUM CARBOXYLATE or WAX-PHENOL CARBOXYLIC non) (3-14) (a) Preparation of sodium carbomylate of warphenol carbon lie acid (3-14) One hundred grams of wax-phenol, prepared as indicated in 1(a) were dissolved in 200 grains of mineral oil (SUV of 45 seconds at 210 F.) followed by adding 100 cc. of butanol and heating the mixture to about 100 C. Then, 2.94 grams of metallic sodium were added in thin strips and,

the mixture was heated at the reflux temperature of butanol until all of the sodium had reacted. Butanol was then distilled therefrom and the temperature was raised to 200 C. whereby the sodium phenate (3-14) was obtained. ,A current of CO2 was-then introduced during a period of about 5 hours to form the mono-sodium salt of wax-phenol carboxylic acid (3-14) (b) Preparation of basic barinm carboaylate of wax-phenol carbowylic acid (3-14) action mixture was then filtered with the aid of I-Ii-Flo to give the basic barium carboxylate of wax-phenol carboxylic acid (3-14) in mineral oil.

(c) Preparation of reaction product of II (b) and mercaptobenzothiaeole Two hundred grams of the mineral oil blend of the basic barium salt obtained in (b) was reacted with 10.28 grams of mercaptobenzothiazole at 130 C. for a 2-hour period, during which water was liberated. The product was homogeneous and soluble in mineral oil. As a measure of the reaction, the alkalinity of the basic barium salt used in the reaction was reduced from 22.3 mgs. of-HCl per gram to 13.3 mgs. of 1101 per gram of reaction product, which is predominantly comprised of the mercaptobenzothiazole reaction product ofbasic barium carboxylate of waxphenol carboxylic acid (3-14) When referred to hereinafter, this product will be described as Product II.

Rssc'rron Pnonucr or Msncar'ronnnzo'rmazopr: AND

BASIC BARIUM Farmers or WAX-PI-IENOL DISUL- rinn (3-14) of benzol.

(a) Preparation of wax-phenol disulfide (3-14) The product was cooled and diluted with 100 cc.

of benzol, followed by the careful addition thereto of 12.3 grams of sulfur monochloride at about 40 C. during a 30 minute period. After stirring the mixture for one hour longer at room temperature, a solution of 3.75 cc. of-water in 50 cc. of methanol was added to precipitate out sodium chloride formed by reaction of the sulfur monochloride with said sodium phenate. The reaction product obtained is wax-phenol disulfide (3-14) in mineral oil.

asearee (b) Preparation of basic bariu'm phenate of waxphenol disulflde (3-14) To the reaction product obtained in III(a) were added 14.6 grams of BaO dissolved in methanol at about C. Methanol was thereafter removed by distilling the mixture to a maximum temperature of 125 C. The methanol-free mixture was Y then filtered with the aid of Flt-Flo to obtain the basic barium phenate of wax-phenol disulfide (3-14) in mineral oil.

(0) Preparation of reaction product of III (b) and mercaptobenzothiazole One hundred grams of the mineral oil blend.

obtained in III(b) were reacted with 2.65 grams of mercaptobenzothiazole by heating the mixture,

at 130 C. for about two hours. Water was liberated during the reaction and the reaction product formed therein was homogeneous and soluble in mineral oil. The basic barium salt of the disulflde used in the reaction had an alkalinity equivalent to 9.6 mgs. of H01 per gram. and the reaction product thereof with mercaptobenzothiazole had an alkalinity equivalent to only 4.1 mgs of HCl per gram. The'reaction product is predominantly comprised of the mercaptoben- REACTION PRODUCT 0F MERcAProBaNzo'rHiAzoLn AND BASIC BARIUM CARBOXYLATE or WAX-PHENOL Cmmoxvmc Acm Drsurrrna (3-14) V (0) Preparation of wax-phenol carboazylicacid disulflde (ii-14) Five hundred grams of the monosodium salt of wax-phenol carboxylic acid (3-14) formed as described in II(a) above, were diluted with cc. To the solution so formed was added 12.7 grams of sulfur monochloride at a rate slow enough to avoid appreciable rise in temperature. After the sulfur monochloride was added, the mixture was stirred for one hour at room temperature, followed by the addition of 4 cc. of water and 50 cc. of methanol. The resulting mixture was heated to about 80 C. whereupon sodium chloride formed in the reaction with sulfur chloride was precipitated out. The product, in mineral oil, is wax-free phenol carboxylic acid disulfide (3-14).

(h) Preparation of basic barium carbon late of wax-phenol carbomylic acid disulflde (3-14) A solution of 32.6 grams of BaO dissolved in methanol was then added slowly to the raction product obtained in Iilia) and the mixture heated to C. to distill off methanol. The methanol-free mixture was then filtered with the aid of Hi-Flo to obtain the basic barium carboxylate of wax-phenol carboxylic acid disulfide (3-14) in mineral oil.

(0) Preparation of reaction product of IV (b) and mercaptobenzbothiazole A mixture of 485 grams of the reaction product obtained in IV(b) and 14.85 grams of mercaptobenzothiazole was heated with stirring for two hours at C. Here again, water was liberated and the reaction product was homogeneous and soluble in mineral oil. The basic barium salt had an alkalinity equivalent to 9.8 mgs. of HCl per gram of product before reaction with mercaptobenzothiazole and the final reaction product had an alkalinity equivalent to only 3.3 mgs. of HCl per gram. Accordingly, the final reaction product is predominantly comprised of the mercaptobenzothiazole reaction product of the basic barium carboxylate of wax-phenol carboxylic acid disulfide (3-14), identified hereinafter as Product IV.

EXAMPLE V REACTION Pnonuor or Mancnr'rosmzornrazorn AND or BASIC BARIUM SALT or rm: DI'IHIOPHOSPHORIC Acm or WAx-Prmnor. (3-14) (a) Preparation of the dithiophosphoric acid of wax-phenol (3-14) erated in the reaction with the formation of a. homogeneous solution which was soluble in mineral oil. In order to reduce the viscosity of the mineral oil blend to a fluidity suitable for proper handling, 100 grams of heavy-mineral oil (SUV 45 sec. at 210 F.) were added, whereby a finished product in approximately a 1:3 blend in mineral oil was obtained.

The basic barium salt reacted with mercaptobenzothiazole had an alkalinity equivalent to 20.7 mgs. of HCl per gram, whereas the final product had an alkalinity equivalent to only 9.9 mgs. of HCl per gram. This indicates that the product, in mineral oil, is predominantly the mercaptobenzothiazole reaction product of the basic barium salt of wax-phenol dithiophosphoric acid (3-14). This product will be referredto hereinafter as Product V.

The pure products may be obtained in the free condition, rather than in mineral oil blends (as in the foregoing examples), by using a light boiling distillate such as Stoddards solvent, keroreaction temperature was then raised to about 175 C. and the mixture was stirred for about one hour at this temperature to complete the reaction. The product at this stage was the aluminum phenate derivative of wax-phenol (3-14).

To said aluminum phenate derivative were added 207 grams of a mineral oil (SUV of 45'sec0nds at 210 F.), followed by the addition of 7.4 grams of P285. This reaction mixture was heated for 4 hours at about 175 C. During the first hour hydrogen sulfide was evolved, but the mixture was heated longer to insure completion of the reaction and the formation of a particularly stable product. The reaction mixture was then cooled to about 100 C. and water was carefully added with stirring to decompose the AlCla-complex. Several washings with water were required to obtain a water extract free of AlCla. Emulsions formed in this water washing operation were broken by adding small quantities of butanol. The product, free of AlCla-complex, was filtered through Hi-Flo and butanol was distilled off under reduced pressure to obtain the dithiophosphoric acid of wax-phenol (3-14) in mineral oil.

(b) Preparation of basic barium salt of the dithiophosphoric acid of wax-phenol (3-14) One hundred grams of the reaction product in solution in mineral oil obtained in V(a) were reacted with 8 grams of barium hydroxide octahydrate (Ba(OH)2.8H2O) at about 150 C. After stirring the reaction mixture at this temperature for about one hour in order to remove all of the water of reaction, the temperature was then lowered to about 80 C., followed by adding 3.73 grams of 139.0 dissolved in methanol to introduce more barium. Part of the methanol was distilled off during the introduction of the BaO-methanol solution; the temperature was then raised to 125 C. to completely remove the remaining methanol. The reaction mixture was then filtered with the aid of Hi-Flo to obtain the finished product which was approximately at 1:2 blend in mineral oil. The product so obtained is the basic barium salt of wax-phenol dithiophosphoric acid (3-14).

(0) Preparation of reaction product of V(b) and mercaptobenzothiazole One hundred grams of the basic barium salt in solution in mineral oil obtained'in V(b) were reacted with 12.8 grams of mercaptobenzothiazole sene, etc., as the diluent in place-of mineral oil; and following the foregoing procedure and finally distilling off said light boiling distillate.

Although the foregoing procedures represent preferred embodiments for the preparation of the compounds or compositions of this invention, other procedures which will be apparent to those familiar with the art may be used. It is to be understood that all such procedures are contemplated herein.

To demonstrate the effectiveness of the compounds or compositions of the type described above by the general Formulae I and II in the mineral oil compositions contemplated herein, we have conducted several comparative tests, the results of which are listed below, with representative mineral oils alone and with the same oils blended with typical and preferred improving agents contemplated by this invention, reaction products of basic divalent metal salts of organic compounds and mercaptobenzothiazole.

POUR POINT DEPRESSION The reaction products of this invention are effective pour point depressants; The following results were obtained from blends of mineral lubricating oils having a SUV of 67 seconds at 210 F. and containing the aforesaid reaction products prepared according to the procedures outlined above. The pour point of the oil alone was 20 F., and as clearly indicated by Table I below, the reaction products contemplated herein are effec- Vrscosrrr Innax Table 11 below shows the effectiveness of the mercaptobenzothiazole reaction products as viscosity improving agents. The oil used in these tests was a motor lubricating oil fraction having a kinematic viscosity of 30.17 at 100 F.

Oran-Ion Trsr In addition to the foregoing tests, comparative.

test runs were made with an oil and an oil blend containing a representative improving agent of the type-contemplated herein under actual operating conditions of an automotive engine. The test was carried out in a single-cylinder C. F. R. engine operated continuously over a time interval of 28 hours, with the cooling medium being kept at a temperature of about 390 F. to give an oil temperature of about 150 F. The engine was operated at a speed of 1200 R. P. M.

The oil used in the test was a lubricating oil having an SUV of 120 seconds'at 210 F., and the conditions observed at the end of the test were: (a) The extent to which the piston rings were stuck; (b) the extent to which the slots in the oil rings were filled with carbonaceous de- 7 posit; (c) the amount of carbonaceous deposits in the oil; and (d) the acidity or neutralization number (N. N.) of the oil. The results from these tests for the blank oil and the same oil containing a small amount of a representative reaction product f the type described above are set forth in Table III below.

It is to be understood that while we have described certain preferred procedures which may be followed in the preparation of the reaction products of mercaptothiazoles and basic polyvalent-metal salts of organic compounds used as improving agents in the mineral oil compositions contemplated by this invention and have referred to various typical constituents in these improving agents, such procedures and examples have been used for illustrative purposes only. The invention, therefore, is not to be construed as limited by the specific examples given but includes within its scope such changes 'andmodiflcations as fairly come within the spirit of the appended claims.

I-claim:

1. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sufilcient to improve the quality of said mineral oil, of an oilsoluble reaction product of a mercaptothiazole and a. basic polyvalent metal salt of an organic compound. characterized by the presence of an aromatic hydrocarbon group substituted with at least one oil-solubilizing alkyl group, said reaction product thereby being characterized by the presence of said aromatic hydrocarbon group and a M-SZ group, wherein M'is a polyvalent metal and Z is a thiazole group. i

2. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, from about per cent to about 5 per cent, of an oil-soluble reaction product of amercaptothiazole and a basic polyvalent metal salt of an organic compound, characterized by the presence of an aromatic hydrocarbon group substituted with at least one oil-solubilizing alkyl group, said reaction product thereby being characterized by the presence of said aromatic hydrocarbon group and a -MSZ group, wherein M is a polyvalent Table III metal and Z is a thiazole group.

Ring condition Per Percent Grams 1 Product added cent Desreesflwck slots filled carbon cone. 1

1 2 a 4 s s 4 5 l None o 360 360 360 360 360 so 90 1o 15 r l s Product In 1 360 0 o o o o 0 o 4.8 "as From the foregoing results it will be apparent that the compounds or reaction products contemplated by this invention are effective multifunctional oil-improving agents. The improved properties obtained and the degree of improvement in a particular property may be varied with the polyvalent metal substituents (M), the thiazole substituents (Z), the substituents represented by the group QM-SZ, the aryl substituents and the degree of substitution of the aryl nucleus with R, Q-MS-Z and Y groups.

The amount of improving agent used may be varied, depending upon the mineral oil or the mineral oil fraction with which it is blended and the properties desired in the final oil composition. The mercaptothiazole reaction products of the type contemplated herein may be used in amounts ranging from A; per cent to 5 per cent, and, in general, compositions of the desired improved properties may be obtained with these improving agents in amounts of from /3 per cent to 1 per cent.

3. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sufiicient to improve the quality of said mineral oil, of an oilsoluble reaction product obtained by reaction of a mercaptothiazole and a basic polyvalent metal salt of an organic compound, said reaction product being characterized by the presence of an alkyl-substituted aryl nucleus and a -M'SZ group, wherein M is a polyvalent metal and Z is a thiazolegroup.

4. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sufilcient to improve the quality of said mineral oil, of an oilsoluble mercaptothiazole basic polyvalent-metal salt of an alkyl-substituted aromatic compound,-

5. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sufficient to improve the quality of said mineral oil, or an oilsoluble i mercaptothiazole basic divalent-metal salt of an alkyl-substituted aromatic compound, said salt being characterized by the presence of an alkyl-substituted aryl nucleus and a M--S-Z group, wherein M is a divalent metal and Z is a thiazole group.

6. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, suflicient to improve the quality of said mineral oil. of an oilsoluble mercaptobenzothiazole basic-barium salt of a waxsubstituted aromatic compound, said salt being characterized by the presence of a waxsubstituted aryl nucleus and a -Ba-S-Z- group, wherein Z is a benzothiazole group.

"I. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sumcient to improve the quality of said mineral oil, of an oilsoluble mercaptobenzothiazole b a sic barium phenate of wax-phenol, said phenate being char acterized by the presence 0! a wax-substituted phenyl group and a --BaS-Z group, wherein Z is a benzothiazole group.

8. An improved mineral oil composition comprising a viscous mineral oil and in admixture therewith a minor proportion, sufl'icient to improve the quality of said mineral oil, of an oilsoluble mercaptobenzothiazole basic-barium carboxylate of wax-phenol carboxylic acid, said carboxylate being characterized by the presence ORLAND M. REIFF. 

